gdk:window-position (window)

window -- a gdk:window object

x -- an integer with the x coordinate of window
y -- an integer with the y coordinate of window

Obtains the position of the window as reported in the most-recently-processed gdk:event-configure event. Contrast with the gdk:window-geometry function which queries the X server for the current window position, regardless of which events have been received or processed. The position coordinates are relative to the window's parent window.